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问题 计算题

有一款手机的主要参数如下表所示，问：

（1）这款手机的平均密度是多少？

（2）如果用某种塑料做一款是实物体积1000倍的“广告手机”，其质量是96kg（已知该种塑料密度为1.2×103 kg/m3），这个“广告手机”是空心的还是实心的？

答案

解：（1）手机体积V=100×48×20×10-9=9.6×10-5 m3，

平均密度ρ=m/V=0.144kg/9.6×10-5m3=1.5×103 kg/m3， 

（2）广告手机的体积V广告机=1000V=1000×9.6×10-5=9.6×10-2 m3，

广告机的密度ρ=m/V=96kg/9.6×10-2m3=1×103 kg/m3

1×103 kg/m3＜1.2×103 kg/m3，所以是空心的。

单项选择题

When I first entered university, my aunt, who is an English professor, gave me a new English dictionary. I was (16) to see that it was an English-English dictionary, also known as a monolin-gual dictionary. (17) it was a dictionary intended for non—native learners, none of my classmates had one (18) , to be honest, I found it extremely (19) to use at first. I would look up words in the dictionary and (20) not fully understand the meaning, I was used to the (21) bilingual dic-tionaries, in which the words are (22) both in English and Chinese, I really wondered why my aunt (23) to make things so difficult for me. Now, after studying English at university for three years, I (24) that monolingual dictionaries are (25) in learning a foreign language.

As I found out, there is (26) often NO perfect equivalence(对应) between two (27) in two language. My aunt even goes so far as to (28) that a Chinese "equivalent" can never give you the (29) meaning of a word in English! (30) , she insisted that I read the definition(定义) of a word in a monolingual dictionary (31) I wanted to get a better understanding of its meaning. (32) , I have come to see what she meant.

Using a monolingual dictionary for learners has helped me in another important way. This dictionary uses a(n) (33) number of words, around 2,000, in its definitions. When I read these definitions, I am (34) exposed to (接触)the basic words and learn how they are used to explain objects and ideas. (35) this, I can express myself more easily in English.

25（）

A. natural

B. better

C. easier

D. convenient
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填空题

向占用区间（），向占用线（），未构成一般B类以上事故的，为一般C类事故。
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